From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 755E63858285; Wed, 7 Feb 2024 19:25:43 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 755E63858285 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1707333944; bh=fAorrYQLAxaKd6D0ENFgVOXUfBwgNNQfk9ARs4sOac4=; h=From:To:Subject:Date:In-Reply-To:References:From; b=k2iQWpwbecoSrHLPiBo/Hp7kUVM6GSXDwhQwDJgXqICxKPAXZ1b2v7BUUl90UQWqG F7xw7ypBwedZc45tO7zi3ps2nObe9A7JyavEruNDGvDbzxCXGhG9QLDPZIsOqgy95n 3etih1RAC3tWVLtWUH+CAR2hq9BSCwg/pV78SkBA= From: "cvs-commit at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/113814] [modules] canonical types ICE with imported partial specialization matching existing template-id Date: Wed, 07 Feb 2024 19:25:41 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c++ X-Bugzilla-Version: 14.0 X-Bugzilla-Keywords: ice-checking, ice-on-valid-code X-Bugzilla-Severity: normal X-Bugzilla-Who: cvs-commit at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113814 --- Comment #1 from GCC Commits --- The master branch has been updated by Patrick Palka : https://gcc.gnu.org/g:ff41862357ca2ea56177209a2e3b7d9c64bcfa8c commit r14-8870-gff41862357ca2ea56177209a2e3b7d9c64bcfa8c Author: Patrick Palka Date: Wed Feb 7 14:24:51 2024 -0500 libstdc++: Work around modules issue causing hello-1 ICE [PR113710] The forward declarations of std::get in added in r14-8710-g65b4cba9d6a9ff are causing an ICE in the test modules/hello-1 due to what seems to be a declaration merging issue in modules. What's happening is that in hello-1_b.C we first include , which indirectly includes which forms the dependent specialization tuple_element<__i, tuple<_Elements...>> (appearing in the signatures of some of the std::get overloads) and adds it to the specializations table. We then import hello which indirectly includes (in the GMF), within which we define a partial specialization of tuple_element with that same template-id. So importing hello in turn streams in this partial specialization but we don't merge it with the previously created dependent specialization, and we end up with two equivalent types for this template-id with different TYPE_CANONICAL. This patch works around this issue by adding a forward declaration of the tuple_element partial specialization from to so that it appears alongside the dependent specialization of the same template-id. So when including we immediately regist= er the template-id as a partial specialization, and if we later stream in = the partial specialization the MK_partial case of trees_in::key_mergeable w= ill match them up. (So perhaps a proper modules fix for this might be to m= ake key_mergeable try to match up a streamed in partial specialization with= an existing specialization from the table via match_mergeable_specializati= on.) PR testsuite/113710 PR c++/113814 libstdc++-v3/ChangeLog: * include/bits/stl_pair.h (tuple_element): Add forward declaration of the partial specialization for tuple. Reviewed-by: Jonathan Wakely =